9 research outputs found
Traceability of raw materials in silos in an anode plant
Carbon anodes, regularly consumed in primary aluminum production, are made of calcined petroleum coke, coal tar pitch, and recycled materials. The properties of calcined coke depend on the source of crude oil and the calcination conditions. Similarly, pitch properties depend on the coal tar source and the manufacturing process. Different calcined coke and pitch mixtures are commonly used in anode manufacturing to meet various regulations and/or due to economics and availability. This makes it hard to maintain the anode quality. Calcined coke and pitch are placed in silos and used when required for production. It is hard for the industries to track the source of raw materials used in their daily recipes. This article presents an approach to trace back the details of the use of particulate raw materials with a custom-made software, which takes into account the type (mass flow or funnel flow) of silos. Such tracking can help identify the causes of problems and maintain/improve anode quality
Linkage entre bancos de dados de nascidos vivos e óbitos infantis em município do Nordeste do Brasil: qualidade dos sistemas de informação
Mortalidade infantil em Cuiabá, Mato Grosso, Brasil, 2005: comparação entre o cálculo direto e após o linkage entre bancos de dados de nascidos vivos e óbitos infantis
Aplicação da metodologia de relacionamento probabilístico de base de dados para a identificação de óbitos em estudos epidemiológicos
Identification of priority areas for conservation in Argentina: quantitative biogeography insights from mygalomorph spiders (Araneae: Mygalomorphae)
On the Young Savannas in the Land of Ancient Forests
Covering ancient geomorphological landscapes, and surrounded by some of the most diverse forests on Earth, the Neotropical savannas were once perceived by naturalists as ancient environments. However, current evidence suggests that tropical forests have existed in the Neotropics since the Paleocene, whereas most plant lineages present in South American savannas are recently derived from clades from the surrounding forested biomes. This chapter provides a multidisciplinary overview on the origin, assembly and expansion of Neotropical savannas, with focus on South America. For this, we consider available evidence from the fossil record, paleoenvironmental proxies (phytoliths), and phylogenetic information for both plants and animals. Paleoenvironmental reconstructions indicate suitable climates for central South American savannas since the middle Miocene, which is also when molecular phylogenies indicate the origin of some vertebrate groups typical of savannas. Fossil data indicate the ecological expansion of both C3 and C4 grasses in southern South America by the late Miocene. Fossil information also indicates the onset of savannas in northern South America during the Pliocene, a period in which most woody plants of the largest extension of Neotropical savannas (the Cerrado) are thought to have diversified, as inferred by dated phylogenies. Although the combined lines of evidence indicate that Neotropical savannas in South America are indeed younger than their surrounding forests, the precise timing and factors that influenced the origin, assembly and expansion of Neotropical savannas remain contentious. Future research should aim at (1) increasing and integrating knowledge about the diversification of important taxa characteristic to Neotropical savannas, (2) establishing continuous sequences of fossils, and (3) building accurate paleoenvironmental reconstructions for the entire Neogene
